More recently, the relative, combined role of different seed formation channels has been extensively investigated in the cosmological pure SAMs presented by [1]}, [2]}, showing that the relative contribution of light, medium-weight and heavy seeds to the assembly of \(z\sim 6\)  SMBHs is determined by a complex interplay between chemical, mechanical and radiative feedback processes in which the mass and redshift distribution of the seeds have a fundamental impact, as they strongly affect the evolution history of the cold gas inside the QSO progenitor galaxies.
